Hzemacytometeb



Dec. 4, 1928. 1,693,961

0. RISCH I HmlA'cYTouETER coum'me CHAMBER Filed Aug. 5. 1926 & W-

mvENTok Osmqe ,Q/sch/ &1, Wk ATTORNEYS Patented Dec. 4, 1928.

UNITED STATES PATENT OFFICE.

OSKAR RISCH, OF JENA, GERMANY, ASSIGNOR TO CLAY-ADAMS 00., INC., 01: NEW

YORK, N. Y., A CORPORATION OF NEW YORK. v

HEMACYTCMETER COUNTING CHAMBER.

Application filed August 5, 1926. Serial No. 127,461.

My invention relates to the type of microscope slides known ashzemacyton'ieter counting chambers, which are employed for the purposeof counting blood corpusclcs. These counting chambers consist of a slidedo of and provided on one of its surfaces in practice that under themicroscope, tl

line. of such network or ruling appear wl or colorless, so that it isdiilicult to see them and effect a proper'count of tie corpuscles. Theobject of my inventionis to overcome this difficulty anu cause the linesof the network or ruling to stand out more prominently, or be darkened.as it were, so that they are readily visible under the microscope.

For this purpose, I provided any optical or other means that willproduce the darkening or visibility-increasing effect above mentioned.The preferred way of carrying out my invention consists in substitutinfor the plane reverse surface of the slide em-- ployed hitherto, aformation that will by refraction or internal reflection cause the linesof the ruling or grating to appear dark or at least more prominent thanwith the former construe ion re red to above.

lieference is be had to the accompany ing drawn g, in which Fig. lies af- 1 view of a hzciuacytometer slide or count: chamber en'ibodving myinvention, F 2 1S cross section on line 2-2 of Fig. l, and Fig. 3 is y aface view of the slide or mounting chamber, looking at'the side oppositeto that shown in 1. It will be understood that the drawing simplyillustrates an example of my invention, and that other constructions maybe employed without departing from the nature duced in the said surfaceand crossing each other. Any of the well-known styles of ruling may beemployed. The opposite l wer) surface or reverse of the body A washitherto made smooth or plane, but in the form of my inventionillustrated herein such r verse surface is provided, in registry withthe rulings or gratings B, with a formation which will cause arefraction or internal redaction of light such as will cause the linesof the gratings to appear more prominently than heretofore. Thisformation may consist. as illustrated, of concave surfaces or sockets Cin register with the respective tings B and acting to produce a lenseelfect. These sockets are preferably produced by grinding, a cylindricalcurvature (of circular arc-shape in cross-section) be ing indicated inFigs. 2 and 3.

Instead of providing the reverse surface lenses, cylindrically orotherwise, I may employ any other formation or any other device, whichwill cause the lines of the gratin or ruling to stand out moreprominently. A stated a; the beginning of this specification, I do notwish to restrict myself to optical means or processes for obtaining thedarkening or visibility-mereasing effect hereinhcfore explained.

It will be understood that generally a slide or counting chamber of thetype herein referred to. is placed in a microscope having arrangementsfor throwing light against the lower surface or reverse ofthc slide andthrough such shoe and the blood deposited on its upper surface.

I claim r l. A haimacytometer slide or I counting chambe pnvicled withruling on one side and with a visibility-increasing formation on theopposite side.

In testimony whereof I have hereuntoset my hand.

OSKAR RISCH.

,J. A hoeinacytoin'etor Slide or counting

